Logging has orangutans on the run in Borneo. But an unappreciated tendency to go to the forest floor and scoot short distances while upright or on all fours gives red apes a chance to survive in patchy, partially destroyed forests, researchers report February 13 in Scientific Reports.

More than 1,400 unobtrusive video cameras recorded 641 instances of orangutan ground travel between June 2006 and March 2013. Orangutans left the trees as frequently in dense forests as in areas hit hard by logging, indicating that this is Bornean orangutans natural behavior, says a team led by veterinarian Marc Ancrenaz of HUTAN/Kinabatangan Orangutan Conservation Program in Sabah, Malaysia.

Ground travel enables orangutans to forage for shoots, termites and other food, Ancrenaz says. Unfortunately, it also makes the apes more vulnerable to hunters and humanborne infections.

Adult males engaged in the most ground travel.

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